experiences with Grado Statement1 &/or Reference1

Is the Reference1 cart a big improvement over the previous line (non-"1" designation)? And is the Statement1 a big jump up from the Reference1, or is the Reference1 only a few increments below the performance of the Statement1? (I would acknowledge that increments really matter when you're deep into the high end; but if the Reference1 is, say, 90% of the way to the Statement1, it would be nice to know that.) I am having trouble finding user reviews of these new "1" Grado carts. Thank you very much.